Effects of SDF on Bonding and MMPs Activity to Dentin

Objectives: To evaluate the bond strength and endogenous enzymatic activity of a universal adhesive with or without dentin pre-treatment with two SDF-based primers. Methods: Deep coronal dentin surfaces were exposed to receive one of the following pre-treatments (n=6): 1) no pretreatment, C; 2) Riva Star, SDF (SDI); 3) Riva Star Aqua, AgF (SDI). A universal adhesive (ZipBond universal, SDI) was used for bonding procedures in the self-etch (SE) or etch-and-rinse mode (E&R) before the restoration with two 2mm-thick increments of a nano-hybrid resin composite material (Luna, SDI). Sticks were obtained per each group and submitted to the microtensile bond strength test (µTBS). Additional 3 teeth per group were used for the in situ zymography evaluation. Data were statistically analyzed (p<0.05). Results: The E&R/C showed the highest µTBS among the groups (p<0.05). In general, E&R performed significantly better than the SE groups (p<0.05), except in the AgF pretreatment where no differences could be found between the two etching modes (p=0.05). In the SE group, AgF performed similar to the C group. Conclusions: At baseline, the effects of the two SDF-based primers are mainly related to the etching mode of the universal adhesive. Although AgF recorded similar results in the SE and E&R groups, further studies are warranted to evaluate the long-term effects.